# HEADER_ALG

> `const` **HEADER\_ALG**: `1` = `1`

Defined in: [packages/filecoin-encryption-envelope/src/cose/constants.ts:19](https://github.com/FilOzone/synapse-sdk/blob/9ad84d812e1dd635b76420a7d9388555a04f31b6/packages/filecoin-encryption-envelope/src/cose/constants.ts#L19)

`alg`, RFC 9052 §3.1. Selects the encryption scheme, see the ALG_* constants.